Ximenia

Ximenia americana is a small, thorny, semi-deciduous shrub or tree, usually 2 to 7 metres tall, with fragrant white to cream flowers. The fruit is an oval drupe 2 to 3 centimetres long that turns from green to yellow or orange-red when ripe, with thin skin and tart flesh. Inside is a single hard stone that holds an oily white kernel. The tree is semi-parasitic, taking water and nutrients from the roots of neighbouring plants, and tolerates hot, dry savanna conditions. The fruit is sour-sweet, while the kernel is bitter in some forms.

The species has a very wide, pantropical range, occurring in dry savanna and coastal regions of tropical Africa, the Americas from Florida through the Caribbean to Brazil, and parts of India, Southeast Asia and northern Australia. It is most important as a food and oil plant in Africa, in countries such as Namibia, Angola, Zimbabwe, Mali and Niger, where it grows wild, and the related Ximenia caffra is common in southern Africa. The genus was named in honour of Francisco Ximénez, a Spanish friar and naturalist.

Across its range Ximenia has been collected for generations as a wild food. The fruits are eaten fresh or made into drinks, jams and fermented beverages, and the kernels are eaten after processing or pressed for oil. Leaves, bark and roots are used in many traditional medicine systems, and the oil has been used for softening leather, lubrication and skin care.

Interest in the kernel oil has grown in recent decades. It contains unusual fatty acids, including ximenynic acid, an acetylenic fatty acid, which attracted interest from the cosmetics industry, and ximenia oil is now sold as a skin and hair ingredient, mainly sourced from wild harvest in Namibia and neighbouring countries by rural cooperatives. Other uses, such as biofuel and food, have been explored, but it remains a small specialty crop.

The ripe fruits are eaten fresh, dried or made into jam, juice, wine and sauces. Kernels are pressed to obtain ximenia oil for cosmetics, soaps and traditional lubricating uses, and they are sometimes eaten in small amounts in rural Africa after roasting or soaking. The wood is aromatic and used for small items, and many parts of the plant feature in local medicine. The oil is mostly used outside food.

Ximenia kernels are rich in oil and contain some protein, and the fruit pulp provides vitamin C and carbohydrates. The oil includes oleic acid and unusual long-chain fatty acids, which are studied for cosmetic properties, though evidence for health effects when eaten is limited. Composition varies a good deal between regions and species, so the nutrition values here are only rough estimates. It should be seen as a traditional wild food rather than a reliable dietary source.